There are a wide variety of applications for which the removable mounting of poles is desirable. For example, it may be desirable to position a deck umbrella at various locations around a deck or swimming pool.
U.S. Patent Application Publication No. 2012/0132779 (Johnson et al.) describes an umbrella mounting system in which a plurality of open cylindrical bases are mounted at various locations around a dock or deck, so that a deck umbrella can be repositioned to provide the most effective shade at a given time of day. The base of the deck umbrella is secured within an inner cylindrical sleeve, which is in turn secured within an outer cylindrical sleeve which can be received by one of the cylindrical bases. Although this arrangement allows the deck umbrella to be easily repositioned, no mechanism is provided for securing the outer cylindrical sleeve within the open cylindrical base, and wind beyond a certain force may lift the umbrella out of the open cylindrical base.
In addition to deck umbrellas, removable mounting of poles to a surface is also desirable in other contexts. For example, removable mounting of poles can facilitate the deployment of selectively positionable fencing, reconfigurable sports goals and nets, as well as pole-mounted cameras and other observational equipment.
One difficulty associated with removable mounting of poles is that in general, making it easier to install a pole at a given location also makes it more likely that the pole may be accidentally displaced, and conversely, the more effectively the pole is secured against accidental displacement, the less convenient it is to install and remove.
For example, Canadian Patent Application No. 2,269,940 (Fretts) teaches a support system for a pole (primarily a utility pole) comprising an anchor including a support member having an internal frusto-conical recess which receives the tapered end of a pole. Holes may be drilled through the support member and lag bolts inserted through the holes and into the pole to secure the pole to the support member. While this effectively secures the pole to the anchor, it makes it cumbersome to install the pole and to remove it if it becomes necessary to do so.